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Beyond the Protein Matrix: Probing Cofactor Variants in a Baeyer-Villiger Oxygenation Reaction.

ABSTRACT: A general question in biochemistry is the interplay between the chemical properties of cofactors and the surrounding protein matrix. Here, the functions of NADP+ and FAD are explored by investigation of a representative monooxygenase reconstituted with chemically-modified cofactor analogues. Like pieces of a jigsaw puzzle, the enzyme active site juxtaposes the flavin and nicotinamide rings, harnessing their H-bonding and steric properties to finely construct an oxygen-reacting center that restrains the flavin-peroxide intermediate in a catalytically-competent orientation. Strikingly, the regio- and stereoselectivities of the reaction are essentially unaffected by cofactor modifications. These observations indicate a remarkable robustness of this complex multi-cofactor active site, which has implications for enzyme design based on cofactor engineering approaches.

SUBMITTER: Martinoli C

PROVIDER: S-EPMC3893305 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Beyond the Protein Matrix: Probing Cofactor Variants in a Baeyer-Villiger Oxygenation Reaction.

Martinoli Christian C Dudek Hanna M HM Orru Roberto R Edmondson Dale E DE Fraaije Marco W MW Mattevi Andrea A

ACS catalysis 20130101 12

A general question in biochemistry is the interplay between the chemical properties of cofactors and the surrounding protein matrix. Here, the functions of NADP<sup>+</sup> and FAD are explored by investigation of a representative monooxygenase reconstituted with chemically-modified cofactor analogues. Like pieces of a jigsaw puzzle, the enzyme active site juxtaposes the flavin and nicotinamide rings, harnessing their H-bonding and steric properties to finely construct an oxygen-reacting center ...[more]

PMID: 24443704

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